Well, that *still* makes professional psychics sound like cheats to me. If I had a special talent that I could not control, then I don't see how I could charge money up front for a session where those talents might show up... but probably wouldn't.
But not everyone who reads cards or does palmreading, etc, claims to be a "professional psychic". And people who DO claim to be perfect psychics are either exceptionally gifted and attuned to their ability to be psychic(which is extremely rare and the people probably don't publicize, seeing as it's migraine-inducing stuff), or full of shit and shouldn't be taken seriously(more common, and more likely).
Everyone is psychic to a point- dreams that come true, knowing who's calling before you answer, predicting TV episodes or movies, etc. People who read tarot know how to trust their natural intuition, and study a long time to understand the cards. As a matter of fact, tools like palmreading(There's actually a science to it) and tarot cards are TOOLS, to help trigger the natural psychic..ness...of people. That's why fortunetellers charge- for the service of using their tool to get a result.